Petersburg lost power Tuesday night for almost two hours after a tree fell into a major powerline five miles south of town. Petersburg Municipal Power & Light crew cut the tree out, freed the line and restored power for all of town around 9:20.
“There’s actually quite a backstory to the situation,” Utility Director Karl Hagerman told KFSK Wednesday morning.
The crew had been working since early Tuesday afternoon to address leaning trees and poles weighed down by snow in different parts of town before the outage started.
While assessing the tree at 5 Mile, they realized it was leaning into a 69,000 volt overhead line that feeds power from Southeast Alaska Power Agency, a regional hydropower supplier that heavily supports Petersburg.
Petersburg also uses power generated from its Blind Slough hydroelectric facility south of town. That circuit is under the SEAPA line, in the same area as the problem tree.
Both power feeds needed to be taken offline to address the problem. But when the crew started preparing to move Petersburg onto diesel power in the meantime, they realized the diesel generator at Scow Bay wasn’t coming online, despite performing normally during a test that morning.
Without it, the borough wouldn’t have the capacity to support Petersburg’s load, especially during peak power usage hours in the evening.
The tree was making contact with the line intermittently as it shed and took on snow. Hagerman decided it would be safer to wait for daylight to address the problem, but that didn’t go according to plan.
“The crew was in the process of standing down, and about 30-40 minutes later, the problem tree decided it was meant to be down,” Hagerman said. “It came back into the line, caused the fault, and that’s when we had the outage.”
He said no one was hurt, and the crew was “able to respond very quickly to the situation” and restore power.
“It’s something we’ll learn from, certainly,” he said.
Hagerman said an engineer was coming back to Petersburg Wednesday to help staff sort out the Scow Bay generator issue.
“I have no reason to believe that our issues with this unit will persist,” he wrote in a follow up email. “With cold weather coming around again this weekend, we plan on having all of our local generators available if they are needed … We appreciate our customer’s patience as they waited in the dark.”
